Design and Implementation of a Documentation Tool for ... - MADOC

winsize, used in chunks 18c, 30a, 31b, and 34c.
Uses chunk11 18c, die 23b, and PTM 28c.
Retrieving the window size requires ioctl.h for ioctl():
31a 〈includes 8b〉+≡ (15b) ⊳ 28f 33b ⊲
#include
The client PTYs window size will be initialized now. This needs to take
place before the client application is launched, because it probably requires
an already configured terminal size when starting up. Writing the size to the
transcript however would put the window size meta chunk before the start of
session chunk, therefore winsize()s mode 1 is used.
31b 〈openpt 31b〉≡
winsize(1);
Uses winsize 30b.
A.10 Running the Target Application
The doshell() function is run in the child process, whose only task is to set up
all required PTY redirections and then execute the client command. Therefore,
open file descriptors from the parent process which are no longer needed are
closed early.
31c 〈doshell 31c〉≡ (15c)
void doshell() {
close(PTM);
fclose(OUTF);
〈change the terminal 31d〉
〈determine the shell 32b〉
〈execute the shell 32d〉
}
Defines:
doshell, used in chunk 9.
Uses OUTF 22a and PTM 28c.
Changing the Terminal
Next, the child process changes its controlling terminal to be the PTY slave. In
order to do that, it has to be placed in a separate session.
31d 〈change the terminal 31d〉≡ (31c) 32a ⊲
setsid();
if (ioctl(PTS, TIOCSCTTY, 0) < 0) {
perror("controlling terminal");
die("controlling terminal failed", 0);
}
Uses die 23b.
31